High
No Switched Live on Potterton Suprima HE

Your boiler has completely lost the electrical signal it needs to start running, meaning it is currently unable to provide any heating or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Internal fuse blown, no mains supply, or faulty control PCB/transformer.

From this model's manual
Verified against the Potterton Suprima He System installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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